Table 1. Classification of heart failure.

Type of heart failure	Clinical evidence	LVEF	Additional evidence
HFrEF	Symptom*±Sign†	≤40%	Not required
HFmrEF	Symptom*±Sign†	41–49%	Not required
HFpEF	Symptom*±Sign†	≥50%	Increase of NP levels or LV structural/functional abnormality suggesting LV diastolic dysfunction or increased LV filling pressure

LVEF = left ventricular ejection fraction; HFrEF = heart failure with reduced ejection fraction; HFmrEF = heart failure with mildly reduced ejection fraction; HFpEF = heart failure with preserved ejection fraction; NP = natriuretic peptide; LV = left ventricular.

^*Typical symptoms: exertional dyspnea, orthopnea, paroxysmal nocturnal dyspnea, fatigue, and pedal edema; Atypical symptoms: weight gain, weight loss, loss of appetite, and palpitation.

^†Typical signs: jugular vein distension and S3 sound; Atypical signs: peripheral edema, rales, irregular heart beat, tachypnea, hepatomegaly, and ascites.